Compressive gaskets need to maintain sealing force over time while under compression. For example, in automobiles, materials are needed that provide low compression set while maintaining a high elongation and high sealing force at service temperatures that may be less than 0° C. A poor quality seal in engine valve cover gaskets leads to increased emissions and reduced engine efficiency, neither of which is desirable.
A number of sealants are disclosed in the art. U.S. Pat. No. 6,274,688 describes a vinyl polymer which has at least one terminal functional group per molecule and has a ratio of weight average molecular weight to number average molecular weight of less than 1.8.
There is a need for compositions which improve sealing or adhesive performance of substrates contacted therewith, particularly engine valve cover gaskets.
There is a need in the art for materials that provide low compression set while maintaining high elongation and high sealing force at service temperatures that may be lower than 0° C.